Since student transportation began, school districts have been challenged with the problem of not knowing which students are on which buses, and bus drivers have struggled with keeping track of their riders and remembering which riders are to embark/disembark at each stop. Schools and transportation departments can receive phone calls several times a week from distraught parents worried about the status of their children, or from parents requesting different transportation arrangements for their children. Systems exist for tracking students as they board school buses, such as using radio frequency identification (RFID) tags carried by each student. Any system that requires much additional action by the driver in the boarding and deboarding process may meet with strong resistance to implementation and can slow buses that must operate on strict route schedules.